Official Skynetic Bison XT STOL Discussion Thread

[Atrix]

Anyone know what these are?

They glue to the end of the wing. I used Foam-Tac glue.

[Warlox]

Anyone know what these are?

[Atrix]

I played around with the remaining wing light unit. It still works all the way down to 3.5 volts and consumes less amps at lower voltages, which may be obvious to those who are better than me at electronics. I was getting 0.4A at 6V, 0.3A at 5V, and as expected 0.2A at 4V. Lower voltages/amps means less bright lights but less heat as well. 4.0 volts seems to be a good compromise between brightness and heat, I was able to leave it powered for 10 minutes while only getting a little warm.

[2much2do]

wow...that sounds immensely disappointing. I really hope Motion doesn't have a complete flop on their hands.

[Atrix]

I maidened the Bison XT this morning at my local field (asphalt runway) on 6S. I went with disconnected slats and threw a FT Aura 5 board in there just to be safe. I started on full manual, passthrough control and full rates (20% expo all around), and ground looped on the first take off attempt, got some road rash on the outside edges of the wings/ailerons. On the next attempt, I was able to power it into the air without flaps. I took it around the field and had to do quite a bit of trimming, especially (oddly) in rudder. Landings were very bouncy and tricky to control on the hard runway, and ground control is almost nil because of the relatively soft springs between the tail wheel and rudder. I got through three batteries without destroying the plane, which is a success in my book. Here are a couple notes:

• The road rash from the ground loop also tore both aileron hinges. The unreinforced foam hinges here are a bit of a disappointment for a bird so beefy everywhere else. Luckily I had hinge tape and was able to field repair. If you get this kit, I would reinforce the aileron hinges before maiden.
• I lost a lock nut in the landing gear, which was surprising, but easily remedied.
• I lost one of the wing light assemblies, despite bending the pins as suggested. The issue was that the light assemblies get pretty hot which shrank the double sided tape and made them loose. As I mentioned in a previous post, I swapped the included light controlled for a regulator, so this may be on me. The regulator is set at 6V, and I am not sure if that contributed to the heat in the wing light assembly. No other LEDs got hot. I removed the other wing light before it fell off and will experiment with different voltages on the desk to see about heat. In any case, use some other means to secure these lights, just as back up.
• Tires and landing gear worked great, despite being tricky on the ground.
• The Bison is pretty power hungry. Even at full flaps (which I set at 30 degrees) I would lose altitude below 50% throttle.

So, all in all, I am happy with the Bison XT.

[MJ4RC]

15x8 - 6S
16x8 - 4S

They shared this during yesterday's stream

Atrix,
Thanks for the prop info and confirming the issue regarding the light controller. I submitted a trouble ticket to Motion RC support. I will probably use a 2S lipo for now to power the light controller. Thanks again.

[MJ4RC]

Small prop for 6s larger for 4s. According to MRC latest video.

Thank you very much.

[2much2do]

Boo for linear regulators. Might go find a small 2s pack for the rare times i want lights.

[Atrix]

A couple hiccups, but I got her put together. Still gluing the tires so I stuck some foam tires on to complete the look.

Also, I can confirm that the light controller does not like 6S, it gets burning hot. I pulled it out and will just direct power the lights with my own regulator or a separate battery. For anyone interested, the light controller puts out 6V.

[Denc23@comcast.net]

Small prop for 6s larger for 4s. According to MRC latest video.

[Atrix]

Hello, Can anyone please answer this question? Thanks in advance.

Prop 15X8 or 16X8 for 6S lipo?

15x8 - 6S
16x8 - 4S

They shared this during yesterday's stream

[MJ4RC]

The bigger prop is for 6s right?

Hello, Can anyone please answer this question? Thanks in advance.

Prop 15X8 or 16X8 for 6S lipo?

[Atrix]

Today is the day.

[AussieHoppy]

Looks very cool, but . . . short takeoffs by means of a little flap and a helluva lot of power are nothing but a cheap party trick. What distinguishes a real bush plane is good manners in VERY slow flight. The weight of this thing makes me wonder if it will fill that bill, but if it will, then you certainly ought to put up some video showing it doing so!

If we can accept this appraisal below, then one would assume it should perform stol as expected. Although I'm not sure what to make of the reference to gyro use lol
Yes, it would be nice to see video proof of very/extreme slow stol capabilities...

With The Bison over 100 test flights on it, we found that you can obtain a better flight envelope than the majority of other brand stol birds, especially if you add a gyro like some other brands.

[AussieHoppy]

AussieHoppy looking at your photos, that most certainly should be called a ShockingCub,

Yup lol yet this Bison has the same hinged slat actuation, not as much travel as the Savage Shock but still, same hinged slat mistake? Apparently the Savage Shock flies very nice and predictably slow with the slats completely removed, which speaks volumes.

.... the leading edge slats are an awesome option but we found that the bison really only needs minimal deflection in them to get the best STOL landings and takeoffs.

And speaking of volumes, to quote from 4923crew (I don't know how I missed this post entirely, thanks for the review 4923crew :) ), it would appear he has already discovered the slats don't work for stol while they actuate pushing the slat's trailing edge upward, my take from this would be to fix them in the trailing edge down position keeping a small gap, just how small the gap needs to be will be the experimental part.

[Scott Ellis]

Looks very cool, but . . . short takeoffs by means of a little flap and a helluva lot of power are nothing but a cheap party trick. What distinguishes a real bush plane is good manners in VERY slow flight. The weight of this thing makes me wonder if it will fill that bill, but if it will, then you certainly ought to put up some video showing it doing so!

[MJ4RC]

Hi everyone, we've updated the manual to include specific callouts for screws. The updated manual can be found HERE.

Thank you very much. 👍

[Aros]

Hi everyone, we've updated the manual to include specific callouts for screws. The updated manual can be found HERE.

[Denc23@comcast.net]

Mine shipped Wednesday, arrive scheduled for Tuesday the 28th.

[2much2do]

Bazza, do you think the bison will be different?